Apparatus and method for plastic lining of conduits



H.l R. CRANE June 5, 1945.

APPARATUS AND METHOD FOR PLASTIC LINING OF CONDUITS Filed may '25,A194:5

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uNnEo STATES PATENT oFFlcE APPARATUS AND METHOD FOR PLASTIC LINING FCONDUITS Hubert R. Crane, Los Angeles, Calif.

Application May 25, 1943, Serial No. 488,467

' 12 Claims. (Cl. 25-38) 'I'his invention is a means and a lmethod forapplying a desired lining of plastic material, for

instance a cement plaster, to the bore wall face of various pipe and/orconduits, more especially, underground or installed iron water mains.

It has long been proposed to apply a desired lining of self-hardening,plastic material to pipe bore faces. Johnson et al. in Patent No.22,654,

of 1859, shows a pulled, plaster spreader, and /tw-v-others followed'themethod of that device, as in Y Newsom, Patent No. 1,548,161, of August4, 1925,

'who claimed a method for rst shaping the plaster on the bore face andtwice compressing the layer. He, in that patent, shows a rigidlyconnected train of mandrel elements with sets of springs as centeringguides which had the unvide a greatly simplified means y.and method, ofthe Newsom leadership, except that the centering means or guides isdisposed well ahead of the body of the cement Vspreader to substantiallyeliminate channelling at the said body, :and excepting thatno plowingblades .are used whichV bodily tear the compressed layer from the boreVface in an effort to rotate the mass layer, but in the present inventiona means is providedI to positively compact the plastic layer: first, toextrude some water and then by a rotation of the compressor or rotarytrowel to thoroughly such a degree as will provide for an early thinactjust as long plows and cut. furrows in the mass loosened from the boreface,4 these furrows t being run into by guides 33 at tail end of the ngblades; then a tube former 24 advanced er the cut up mass. te Patent No.1,951,221, of March 13, 1934 issue No. 21,164, of July 25, 1939),closely ,foled the spreading and the successive compresstep method ofNewsom and the several u of the reissue patent disclose a train of cecombination connected with a universal t or for a universal jointfunction to faciliuse of his several guides and the spreader ne a curvedpipe. Tate yfollowed Hune, Patent 11,768,451, in the idea of dehydratingthe plasayer.

tioned, rhas a serious objection in that it found there was `formed atthe bottom` of laidlplaster an accretion of water and ilne `nt whichhardened into a iiat, chordal bed reduced the coeilicient of, flow.Scotts Patl o. 2,293,365, of 1942, aimed to reduce this ed in the borepassageway. Scott employs ate dehydrator and shows no means to elimi-lthe fiat bed unless as by a thick plaster, and

view of this state of the art, and current ce, it is an object of thisinvention to pro-v was in the ken of any of the prior art apowever theapparatus, in the state of the art ning and flushing out of the excesswater and vide a method and means in and by which a` iinal smoothing orsemi-polishing is effected on the compacted plastic layer in a .rotativefunction and gliding or sliding manner without circumferentially turningthe laid plaster lining, and instead of furrowing the lining to give itas slick a surface as may be practical to obtain as high a flowefiiciency in the,` passageway as may be possible on a cement lining.

The invention consists in certain advancements in the art of pipe liningas set forthin the ensuing disclosure and having, with the above,additional objectsfand advantages as hereinafter developed, and whoseconstruction, combinations, and details of means and thermanner ofoperation, and the method, will be made manifest in the ensuingdescription of the herewith illustrative apparatus; it beingv understoodthat modiflcations, variations'fand adaptations may be resorted towithin the scope, spirit and prlnciple of the invention as it is moreparticularly claimed in the addendum. A

Figure 1 is a side elevation of the composite guide, spreader andtrowelling tool (as in use).

a though, of course, it is not so limited in held member the saidforward end of which is flared or conical as shown at 4 and of a muchatter angle than is the leading nose 3; this composite leading memberbeing oi any suitable construction and being suitably. iixedly attachedto the near end of the draft rod series R. When the tool is to be usedthe passageway of the pipe P is suitably charged withra requisite volumeof cement plaster C'.

The diameter of the body member 5 is such that as the cement is crowdedup all around the conical parts lthereof a somewhat compressed annularlayer L of plaster is forced to the face of the pipe bore. The ram 2 andthe nose 3 cooperateto push ahead and out toward the pipe face theencountered mass of plaster and the conical fore end of the body 5 tendsto center this distributing and partial compression member but it isdesired that a, positive mechanical device be combined to more quicklyand more certainly center the distributing body 5. To do this amulti-legged spider B is xed securely at the front end of the ram 2,which is of considerable length, and is of such maximum spread that thebody member 5 is held closely on the line of the axis of the pipe P. Thespread toes 1 of the spider 5 are preferably disposed so far ahead ofthe distributing are 4 of the body 5 that any channels which may be madeas a result of the forward movement of the spider in the plaster arequickly filled up and obliterated by the dispersing effect head I3 witha central mouth I4.

that this leading trowel 8, since it closely follows the firstcompressing member l plants much sediment from the extruded water atzone A into the bottom half of the arc Aoi' the circular lining, butprovision is made for running oi! the clear water-by way of theopen-ended barrel trowel; the rear end being open as well as the front.

Diiferent cases and jobs, and different plastics may require differenttreatment and therefore one or more of rotary trowels (or barrels) maybe employed. It is preferable that at least two rotary barrel trowels beincorporated in the tool, so that a great advantage may be obtained ofhaving one rotate in one direction, as to the right by the first trowel9, and to the leftl as by a second barreltrowel I 2 which is Chollow andopen from end to end and has a frontal, hemispherical The trowel l2 isfreely rotatively mounted as by bearings I5 on the shaft 8, and whichare constructed water ,f proofin suitable m nner..

A feature of the second, or trailing barrel trowel I2 is that its rearsurface portion for a suitable length longitudinally of the body isvmade perfectly smooth annularly, almost polished, for the purpose ofimparting a very smooth f and hard-compacted surface to the plasterlinof the body nose 3 and the distributor cone I and therefore when thelarger cylindric body part shaft, and at a suitable space back of themember 5, is a, hollow, cylindrical, elongate and somewhat larger sizethan the cylindric member 5 for the purpose of additionally compressingthe annular layer of plaster rst bedded onto the bore face by the member5.

As the layer or lining of plaster encountered by the leading trowel 9may have a considerable water content the forward end of the trowel 9 isprovided with a nearly hemispherical head i@ having a frontal mouth I 0of circular outline and as this head follows the compressor body member5 any water squeezed out of the already laid lining collects in fron-tof the head I Ii and the heavy bottom sediment between the member 5 andthe head lil is forcibly trowelled into the bottom area ofthe annularlining L. Any excess ,water and unsettled fine cement can now flow backthrough the hollow, barrel-like leading trowel 9. 'A noticeable featureof this invention is the provision of means to effect a positiverotation of the barrel trowel 9 as it is pulled along the plaster liningin the pipe.

Such rotation is here accomplished by slightly riiling or grooving thesmooth face of the trowel 8 as by suitably pitched, helical channels Ildisposed longitudinally in the periphery of the trowel 9, which, asstated, is rotative on the shaft: the channels opening at their frontends into the equatorial line of the head i0, or the front end line ofthe cylindrical trowel. The resistance of the compressed lining L ofplaster reacts Vto cause the trowel 9 to turn screw-fashion andtherefore to compress and to smooth the engaged surface of the plasticlining. It is to be especially noticed smooth-faced compressing trowel9, preferably of ing. This smooth area is shown at I6 and forwardly fromit extends helical rifling or channels in the body to generate thedesired rotation ofen. the rotary, trowel 'as it is pulled along behind'the leading trowel 9; the trailing trowel i2 being somewhat larger indiameter than its leader to give final compression to the practicallydehydrated lining.

The rotary trowelling combined with themultistage compression produces adensely compacted lining from which lmost of the water has beenextruded, and the fine slimes of the cement are driven into the layer bythe combined forward sliding and the angular rotation of the dressingtrowels 9 and l2, and especially the ilnishing face trowel zone I6. Y

'Ihe slight rifling of the membersgives an increased line of girth andtherefore gives the member a larger surface of dehydratlng effect.

What is claimed is:

1. The steps in lining a horizontal cosglth a plastic, which consists oflaying abate tic along the bottom of the conduit.I o' then subjectingthe plastic to dispersi the bore face of the conduit concentrii jectingthe concentric lining to an eve. compacting en'ort by advancing a cylin1axially therein, and then givingthe fa compacted lining a rotarytrowelling b: ing the lining face to action of a freely` axially moving,cylindric trowel.

2. The method of claim 1, and finally lining face a surface finishingoperatiy jecting it to action offan axially moi rotative, cylindrictrowel part.

3. A conduit' lining tool having, in co aplastic dispersing andcompacting n cluding a cylindric body the fore end m has aconic'disperser, and a, centering sp idly fixed to said disperser andwhose 1 minate well ahe'adbf said bodyand adia that the plastic isdispersed at a, point ri i me of the said toes and track voids areoblite m the dispersed plasticand a trailing, nonfg ing trowel turnablyhitched tothe said!I and having means to effect rotation of th LAconduit plaster working tool hi combination, a freely rotative, liningface smoothing, trowel device, said device having a body with agenerally smooth, cylindric eiiective face which is provided withshallow helical channels to effect trowel rotation while the trowelsmooths the lining face.

5. 'A bore plastering tool having a freely rotative trowel, and which isprovided `with an external shallow, helically grooved area and a finaldressing area.

6; A conduit plastic applying tool for bore use including a body memberhaving a smoothing face helically channelled to eiiect rotation of themember while it is smoothing the face of the lining.

7'. A conduit lining tool having, in combination, a plurality ofcylindric, compacting trowels which are freely relatively rotative andhave rotation effecting means, and means to iinally smooth out thetroweled face.

8. Acondult lining tool having,in.'combina'` tion, a plurality ofrotative, cylindric, smoothing trowels, and non-grooving work controlledmeans for effecting rotation of the trowels;

9. A bore surface working tool having a plurality of cylindrie trowels,said troweis having relatively reversed, helical grooving.

l0. A conduit lining tool having, in combination, a` joined train ofcylindric, plastic compacting members which are clearly spaced axiallyfor dehydration of the plastic and are open fromv end to end for by-passof extruded waten g 11. The tool of claim l0; certain of said membersbeing freely rotative;

. 12. The tool of claim" 10; certain of the members being provided intheir compacting surfaces with shallow helical grooves to effectrotation thereof while compacting the face of the applied lining.

HUBERT R.. CRANE.

